Research And Preparation Of Ultimate Current-Type Oxygen Sensor

In the automotive sector,solid-state electrolyte oxygen sensors have been playing an important role since the chip-type limit current-type oxygen sensor has a wide measuring range and is quite accurate in measurement accuracy and does not require any reference gas.It has been regarded as the core components of oxygen meter,especially the type of oxygen sensor in high temperature and humidity environment to show the excellent working characteristics of the researchers are widely studied and applied.In this paper,based on the exploration and research on the preparation process of the dense diffusion current limit type current sensor,the electronic conductivity of the material and the ionic conductivity,sintering process and signal detection are studied by means of casting co-firing On the basis of domestic and foreign research,to carry out a new exploration and to explain its conductive mechanism.The LaSrMnO₃?LSM?powders were prepared by conventional solid phase method.The samples were subjected to conventional sintering,and XRD,line shrinkage,SEM,and conductivity were tested and analyzed for a series of physical properties and sensitive electrochemical properties.Based on the comprehensive test results,it is deduced that the optimum sintering temperature of LSM used as solid electrolyte is about 1050 ?.The LSM and 8YSZ stripes were tested for the conductivity of dry air and helium by the four-terminal resistance method.It was found that the electrical conductivities of LSM and 8YSZ were 99.7% and 0.03% of the total conductance at 700 ?,respectively.Using the casting process,8% molY₂O₃ stabilized ZrO₂?Yttria Stablilzed Zirconia?8YSZ)and LSM castings were used to prepare the sensor embryo by casting process,followed by the use of platinum wire as the sensor electrode And then use the glass glaze seal,and finally sintered again to obtain the required dense diffusion limit current oxygen sensor;the use of scanning electron microscopy?SEM?and other means of the physical performance of the oxygen sensor,and then the oxygen sensor in the operating temperature range of 0 % 21% oxygen concentration of oxygen sensitivity test and study its mechanism,while testing and analysis of the electrolyte operating temperature on the limit current size of the impact.The experimental data obtained by the test show that the oxygen sensor prepared by the casting process has a good saturation platform in the range of 0% 21% oxygen concentration,and it is found that the current and oxygen concentration And the linearity of the normal diffusion model.At the same time,with the deepening of the experiment,it is found that there is a certain relationship between the limit current and the thickness of the dense diffusion barrier,and the current decreases with the increase of the density of the dense diffusion barrier.Still have a certain saturation platform.